Auto merge of #22045 - asajeffrey:magicleap-follow-hyperlinks, r=paulrouget

Get the ML port to follow hyperlinks

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This PR adds some basic mouse support to the magic leap touchpad. Moves are mapped to mouse moves (for hover style) and trigger pulls are mapped to mouse clicks (for following hyperlinks).

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because we can't test on ML

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ports/libmlservo/src/lib.rs

@@ -12,8 +12,10 @@ use servo::BrowserId;
 use servo::Servo;
 use servo::compositing::windowing::AnimationState;
 use servo::compositing::windowing::EmbedderCoordinates;
+use servo::compositing::windowing::MouseWindowEvent;
 use servo::compositing::windowing::WindowEvent;
 use servo::compositing::windowing::WindowMethods;
+use servo::embedder_traits::EmbedderMsg;
 use servo::embedder_traits::EventLoopWaker;
 use servo::embedder_traits::resources::Resource;
 use servo::embedder_traits::resources::ResourceReaderMethods;
@@ -25,8 +27,10 @@ use servo::euclid::TypedSize2D;
 use servo::gl;
 use servo::gl::Gl;
 use servo::gl::GlesFns;
+use servo::script_traits::MouseButton;
 use servo::servo_url::ServoUrl;
 use servo::style_traits::DevicePixel;
+use servo::webrender_api::DevicePoint;
 use smallvec::SmallVec;
 use std::ffi::CStr;
 use std::ffi::CString;
@@ -98,6 +102,61 @@ pub unsafe extern "C" fn heartbeat_servo(servo: ServoInstance) {
     // Servo heartbeat goes here!
     if let Some(servo) = (servo as *mut Servo<WindowInstance>).as_mut() {
         servo.handle_events(vec![]);
+        for ((_browser_id, event)) in servo.get_events() {
+            match event {
+                // Respond to any messages with a response channel
+                // to avoid deadlocking the constellation
+                EmbedderMsg::AllowNavigation(_url, sender) => {
+                    let _ = sender.send(true);
+                },
+                EmbedderMsg::GetSelectedBluetoothDevice(_, sender) => {
+                    let _ = sender.send(None);
+                },
+                EmbedderMsg::AllowUnload(sender) => {
+                    let _ = sender.send(true);
+                },
+                EmbedderMsg::Alert(_, sender) => {
+                    let _ = sender.send(());
+                },
+                EmbedderMsg::AllowOpeningBrowser(sender) => {
+                    let _ = sender.send(false);
+                },
+                // Ignore most messages for now
+                EmbedderMsg::ChangePageTitle(..) |
+                EmbedderMsg::BrowserCreated(..) |
+                EmbedderMsg::HistoryChanged(..) |
+                EmbedderMsg::LoadStart |
+                EmbedderMsg::LoadComplete |
+                EmbedderMsg::CloseBrowser |
+                EmbedderMsg::Status(..) |
+                EmbedderMsg::SelectFiles(..) |
+                EmbedderMsg::MoveTo(..) |
+                EmbedderMsg::ResizeTo(..) |
+                EmbedderMsg::Keyboard(..) |
+                EmbedderMsg::SetCursor(..) |
+                EmbedderMsg::NewFavicon(..) |
+                EmbedderMsg::HeadParsed |
+                EmbedderMsg::SetFullscreenState(..) |
+                EmbedderMsg::ShowIME(..) |
+                EmbedderMsg::HideIME |
+                EmbedderMsg::Shutdown |
+                EmbedderMsg::Panic(..) => {},
+            }
+        }
+    }
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn cursor_servo(servo: ServoInstance, x: f32, y: f32, trigger: bool) {
+    // Servo was triggered
+    if let Some(servo) = (servo as *mut Servo<WindowInstance>).as_mut() {
+        let point = DevicePoint::new(x, y);
+        let window_event = if trigger {
+            WindowEvent::MouseWindowEventClass(MouseWindowEvent::Click(MouseButton::Left, point))
+        } else {
+            WindowEvent::MouseWindowMoveEventClass(point)
+        };
+        servo.handle_events(vec![window_event]);
     }
 }